1. Field of the Invention
The present invention relates generally to the field of molecular biology. More particularly, it concerns compositions for and methods of nucleic acid repair.
2. Description of Related Art
There are several commercial formulations that use T4 DNA Polymerase (T4Pol) and T4 Polynucleotide Kinase (T4PNK) to repair DNA ends prior to ligation for the purposes of cloning or Next Generation Sequencing (NGS). Some formulations also include the Large Klenow fragment of E. coli DNA Polymerase I (Klenow) to facilitate complete extension of 3′ recessed ends and to prevent over-trimming by the 3′ exonuclease activity of T4Pol. Very little attention has been paid to a different form of damage that involves the presence of a phosphate group at the 3′ terminus of DNA. Ends containing a 3′ phosphate are not extendable and not competent for ligation. The removal of the 3′ phosphate is critical for successful and efficient end-repair. Generally, the removal of the 3′ phosphate is left to the rather weak 3′ phosphatase activity of T4PNK.